Martin St. Louis (second from left), whose mom, France, died Thursday, celebrates with Rangers teammates after a goal in their 5-1 win over the Penguins in Game 5 Friday night in Pittsburgh. Photo: Paul J. Bereswill

PITTSBURGH — Martin St. Louis has been part of the Rangers family for just over two months. But when tragedy struck, St. Louis chose to stand with this family and with his teammates, in what could have been the Blueshirts’ last stand of the year — but was not.

On this night of unimaginable sorrow one day after the passing of his mother, it was as if France St. Louis were looking over her son and his friends.

Rangers 5, Penguins 1 in Friday’s Game 5 means Game 6 at the Garden on Sunday … 7 p.m. on Mother’s Day.

“We are a team, and a close team, and in the short time Marty has been here he has been pretty magnetic,” Brian Boyle, a major contributor, said following the victory in which the Rangers played with passion and pride. “He’s a special person.

“There’s a love we have for him.”

St. Louis learned of his mom’s passing after arriving here with his team on Thursday. He immediately went to Montreal to be with his family and decided Friday morning to rejoin his club — to rejoin his second family — after having been told by coach Alain Vigneault that, “There are more important things than hockey … you have to do what’s right … you have to take care of your dad.”

What was right for St. Louis was to follow his heart and return to Pittsburgh for this hockey game. It doesn’t make him a hero. He didn’t pretend to be one after Game 5 had ended. It makes him human, is what it does.

“I knew deep down my mom would want me to play this game and be proud of me coming here to help as much as I can,” the 38-year-old native of Laval, Quebec, said. “I’m thankful for the time I got to spend with my father [on Thursday] and I know he’s proud of me like my mom is proud.

“She was a great lady, best human being I’ve ever known in my life. I owed it to her to do it. I know she would want me to do it.”

The Rangers were, in the vernacular of sports, playing for their lives. So perhaps their passion and urgency would have come naturally in any event. The core of this team that has been together for the last three playoffs, 10 in all, had won seven of nine previous games while facing playoff elimination. Now it’s eight out of 10.

But perhaps the sight of St. Louis in the room galvanized this club that hadn’t come close to resembling the team that was, in fact, a pretty darn good one during the regular season and a fairly good one in the seven-game first-round victory over the Flyers.

Perhaps there was an angel looking down on the Blueshirts.

“She was patting my fiancé’s belly 10 days ago,” said a somber Brad Richards, St. Louis’ very good friend whose fiancé, Rechelle Jenkins, is expecting. “Our families lived in Florida for a long time, so we were close and I knew her very well.”

It has been only two months, but the Rangers family has gotten to know St. Louis very, very well. It is the measure of the man that he feels such loyalty to his teammates. It is the measure of his teammates that the feeling is mutual.

“Honestly, I know that the team told him not to feel like he should come, and then to see him in the locker room, and watch the way he was preparing for the game, it was a very emotional experience for me,” said Derick Brassard, who recorded two goals and an assist, sent five shots on net and was credited with six hits, and all in 13:47. “The day before when we got the news, I think we all would have gone with him [to Montreal] if we could have.

“I didn’t know him at all before; there’s an age difference,” added the 26-year-old native of Hull, Quebec. “But I was really excited when I found out we got him in the trade; he’s probably the best player of my time [from Quebec].

“To be able to see the way he prepares and the way he competes every day, in practice and the games, it’s special for me.”

Surrounded by friends and family, supported by friends and family, St. Louis competed in Game 5. The rink was his sanctuary.

“It’s always like that for me,” said France St. Louis’ son. “Once I got on the ice, I’m not saying I forgot, but it’s probably the most comfortable place there can be for a hockey player.”

Friday night, an angel was looking down upon the ice. Game 6 on Mother’s Day.